| Parameter |
Value |
| Designation |
C/2003 A2 (Gleason) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
2003-11-05T00:23:36.450240Z |
| Orbit solution date (soln_date, UTC) |
2025-07-31T12:12:22Z |
| Obs used |
165 |
| NEO |
- |
| M1 |
6.500 |
| K1 |
7.500 |
| PC |
0.030 |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
2003-08-08.0000000 |
| e |
1.00694108 |
| q (au) |
11.427006 |
| a (au) |
-1646.285863 |
| i (deg) |
8.061536 |
| Ω (om, deg) |
154.544669 |
| ω (w, deg) |
346.638010 |
| M (ma, deg) |
-0.001313 |
Magnitude
Scatter + Global Linear
$$
M_a = (-2.179 + 6.000\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
-2.179 |
| n |
6.000 |
| gf |
0.898 |
| gb |
-0.974 |
| k |
1.000 |
| δ90 |
4.460 |
| Parameter |
Symbol |
Range |
Description |
| Absolute magnitude at 1 AU from Sun and Earth |
H0 |
-5 to 20 |
Intrinsic brightness of the comet |
| Photometric slope parameter |
n |
2 to 6 |
Rate of brightness change with heliocentric distance |
| Forward scattering asymmetry factor |
gf |
0.8 to 1 |
Degree of forward scattering |
| Backward scattering asymmetry factor |
gb |
-1 to -0.5 |
Degree of backward scattering |
| Partitioning coefficient |
k |
0.8 to 1 |
Ratio between forward/backward scattering contributions |
| Dust-to-gas brightness ratio |
δ90 |
1 to 10 |
Relative contribution of dust scattering to gas emission |
Reference: EPSC-DPS2025-160
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-05-12 00:00 |
16:55:26.81 |
-14:22:58.9 |
HIP 82701 |
16.78 |
| 2026-05-12 12:00 |
16:55:24.19 |
-14:22:52.0 |
HIP 82701 |
16.14 |
| 2026-05-13 00:00 |
16:55:21.56 |
-14:22:45.1 |
HIP 82701 |
15.49 |
| 2026-05-13 12:00 |
16:55:18.93 |
-14:22:38.2 |
HIP 82701 |
14.84 |
| 2026-05-14 00:00 |
16:55:16.27 |
-14:22:31.4 |
HIP 82701 |
14.19 |
| 2026-05-14 12:00 |
16:55:13.61 |
-14:22:24.7 |
HIP 82701 |
13.54 |
| 2026-05-15 00:00 |
16:55:10.94 |
-14:22:17.9 |
HIP 82701 |
12.89 |
| 2026-05-15 12:00 |
16:55:08.26 |
-14:22:11.2 |
HIP 82701 |
12.23 |
| 2026-05-16 00:00 |
16:55:05.56 |
-14:22:04.5 |
HIP 82701 |
11.57 |
| 2026-05-16 12:00 |
16:55:02.86 |
-14:21:57.9 |
HIP 82701 |
10.91 |
| 2026-05-17 00:00 |
16:55:00.15 |
-14:21:51.3 |
HIP 82701 |
10.24 |
| 2026-05-17 12:00 |
16:54:57.42 |
-14:21:44.8 |
HIP 82701 |
9.58 |
| 2026-05-18 00:00 |
16:54:54.69 |
-14:21:38.2 |
HIP 82701 |
8.91 |
| 2026-05-18 12:00 |
16:54:51.95 |
-14:21:31.8 |
HIP 82701 |
8.24 |
| 2026-05-19 00:00 |
16:54:49.20 |
-14:21:25.3 |
HIP 82701 |
7.57 |
| 2026-05-19 12:00 |
16:54:46.44 |
-14:21:19.0 |
HIP 82701 |
6.90 |
| 2026-05-20 00:00 |
16:54:43.68 |
-14:21:12.6 |
HIP 82701 |
6.23 |
| 2026-05-20 12:00 |
16:54:40.90 |
-14:21:06.3 |
HIP 82701 |
5.55 |
| 2026-05-21 00:00 |
16:54:38.12 |
-14:21:00.0 |
HIP 82701 |
4.88 |
| 2026-05-21 12:00 |
16:54:35.33 |
-14:20:53.8 |
HIP 82701 |
4.21 |
| 2026-05-22 00:00 |
16:54:32.53 |
-14:20:47.7 |
HIP 82701 |
3.54 |
| 2026-05-22 12:00 |
16:54:29.73 |
-14:20:41.5 |
HIP 82701 |
2.88 |
| 2026-05-23 00:00 |
16:54:26.92 |
-14:20:35.4 |
HIP 82701 |
2.22 |
| 2026-05-23 12:00 |
16:54:24.10 |
-14:20:29.4 |
HIP 82701 |
1.60 |
| 2026-05-24 00:00 |
16:54:21.28 |
-14:20:23.4 |
HIP 82701 |
1.07 |
| 2026-05-24 12:00 |
16:54:18.45 |
-14:20:17.5 |
HIP 82701 |
0.81 |
| 2026-05-25 00:00 |
16:54:15.61 |
-14:20:11.6 |
HIP 82701 |
1.07 |
| 2026-05-25 12:00 |
16:54:12.77 |
-14:20:05.7 |
HIP 82701 |
1.61 |
| 2026-05-26 00:00 |
16:54:09.93 |
-14:20:00.0 |
HIP 82701 |
2.23 |
| 2026-05-26 12:00 |
16:54:07.08 |
-14:19:54.2 |
HIP 82701 |
2.89 |
| 2026-05-27 00:00 |
16:54:04.22 |
-14:19:48.4 |
HIP 82701 |
3.57 |
| 2026-05-27 12:00 |
16:54:01.36 |
-14:19:42.8 |
HIP 82701 |
4.25 |
| 2026-05-28 00:00 |
16:53:58.50 |
-14:19:37.2 |
HIP 82701 |
4.94 |
| 2026-05-28 12:00 |
16:53:55.63 |
-14:19:31.6 |
HIP 82701 |
5.63 |
| 2026-05-29 00:00 |
16:53:52.76 |
-14:19:26.1 |
HIP 82701 |
6.33 |
| 2026-05-29 12:00 |
16:53:49.89 |
-14:19:20.7 |
HIP 82701 |
7.02 |
| 2026-05-30 00:00 |
16:53:47.01 |
-14:19:15.3 |
HIP 82701 |
7.72 |
| 2026-05-30 12:00 |
16:53:44.13 |
-14:19:09.9 |
HIP 82701 |
8.42 |
| 2026-05-31 00:00 |
16:53:41.24 |
-14:19:04.6 |
HIP 82701 |
9.12 |
| 2026-05-31 12:00 |
16:53:38.36 |
-14:18:59.3 |
HIP 82701 |
9.82 |
| 2026-06-01 00:00 |
16:53:35.47 |
-14:18:54.1 |
HIP 82701 |
10.53 |
| 2026-06-01 12:00 |
16:53:32.58 |
-14:18:49.0 |
HIP 82701 |
11.23 |
| 2026-06-02 00:00 |
16:53:29.69 |
-14:18:43.9 |
HIP 82701 |
11.93 |